Excavator



Aug. 17, 1937.

T. c. WHISLER Filed June 24, 1956 EXCAVATOR 7 Sheets-Sheet 1IISIIVENTOR.

77700755 C. W/7/I5/9r A TTORNEY 7 Sheets-Sheet 2 T. C. WHISLER EXGAVATORFiled June 24, 1936 Aug. 17, 1937.

INVENTOR. 7/20/7755 C. Wh/Is/e/ Bi/M 1 ATTORNEY 5 W v g 5 n u. 5

Afig. 17, 1937. T. c. WHISLER I, 2,090,563

EXCAVATOR Filed June 24, 1936 7 Sheets-Sheet 3 IN VEN TOR. 7A amas C.W/w's/er Augljl 7, 1937. T. c. WHISLER 2,090,563

EXCAVATOR Filed June24, 1936 7 Sheets-Sheet 4 B) 7;: afgg ATM/6ND Aug.17, 1937. 1', c, w s 2,090,563 I EXCAVATOR Filed June 24, 1936 7Sheets-Sheet 5 #wtwroz 7/70/7755 C. Whis/er Aug. 17, 1937. c, WHISLER'2,090,563

-- Aug. 17, 1937. T, WHI LER 2,090,563

EXCAVATOR Filed June 24, 1936 7 Sheets-Sheet 7 gmzim Patented Aug. 17,E937 EXCAVATOR Thomas C. Whisler, Berkeley, Calif.

Application June 24,

6 Claims.

My invention relates to devices which are moved by power into a body ofearth to dislodge the earth and retain it for transportation to anotherpoint. Depending largely upon the type of power mechanism utilized toorient and propel the excavator are the details of the design and theparticular name given to the excavator. In the power shovel field acup-like excavator mounted at the end of a dipper stick is. usually 10referred to as a dipper, whereas in the dredg- 13 of my invention makeit applicable to all fields of use, I have chosen to describe it hereinparticularly in connection with its adaptation to dredge installations.

It has become common practice in dredge construction to make the dredgebucket in two general parts. The first of these is a combined hood andback, forming a cup-like structure having pivot pin connections to otherstructures of like character forming a chain or line of buckets arrangedin an endless loop and having an upper run and a lower run extendingbetween upper and lower tumblers. The combined hood and back or base aresometimes referred to as a bucket body and almost invariably arecast inone piece of manganese steel. Cast manganese steel has been almostuniversally adopted for this use, although the limits or tolerancesnecessary in manufacture are relatively large, and machining aftercasting is virtually restricted to superficial'grinding operations. Evenso, all separate parts must be designed to fit so snugly and tightlywhen assembled that, even after reasonable wear, they will resistany'material relative movement therebetween which would cause greatlyaccelerated wear. While a bucket body is subject to a great deal ofvibration and abuse in dredging service,

it is not subject to a great deal of abrasive wear and hence isdesignedand expected to remain assembled and in service without seriousdeterioration-or diificulty over a protracted period. Bucket bodies varyconsiderably' in capacity, contour, relative size, dimensions, and otherfactors, depending upon their particular design for conditions underwhich they are used, but in general they all terminate in asubstantially elliptical or approximate'ly elliptical margin. If thismargin were directly to excavate and encounter the' abrasive materialdredged, it would. very quickly wear and make necessary the replacementof the entire bucket body.

1936, Serial No. 86,992

This difilculty is precluded by the second general bucket part, which isa separate lip, following approximately the contour of the bucket marginpreferably for more than a half ellipse in extent and in generalextending the contours of the bucket, and fastened to the bucket bodywith a greater or lesser degree of removability. The usual method offastening is -to provide rivets through overlapping portions of the lipand the bucket, but riveting is not entirely satisfactory. It requires arelatively long time for installation, together with special rivetingequipment at the point of installation, while probably the worstdrawback is that the rivets, under the severe service to which theexcavators are subjected, do not continue for long to hold the liptightly in engagement with the bucket body. As soon as some creeping orworking movement begins, due to looseness and wearing of the rivets, therelative movement between the lip and the bucket body becomesprogressively greater, the vibration and shaking become tremendous, andbefore long the lip is so loose on the bucket body that it must beremoved and replaced or reriveted. This operation at the least entailscutting out the worn rivets and reriveting the lip in place. But a greatdeal of other damage is often done, since the loose rivets likewiseaccelerate the wear in the bucket body itself which is thus seriouslydamaged and must be expensively repaired prior to the installation of anew lip.

The riveting and cutting out of rivets and the general difficulties ofremoval and installation are in many instances increased since some lipscarry an outside flange or apron which overlies the outer periphery ofthe dredge bucket body, some 'lips carry an inner flange or flangeswhich overlie all or part of the inner surface of the bucket body to actas reinforcements, and some lips are provided with both inside andoutside flanges. In addition to all of this, it many times occurs thatonly a few buckets in an entire bucket line need repairs or have to havetheir lips replaced, and it is for that reason especially and under allcircumstances highly desirable to be able to replace the lip on a bucketbody without in any wise removing the bucket body from the bucket line,hence making it necessary to remove the old lip and to apply the new lipby,; operating between successive buckets in place in 'the line. It istherefore an object of my invention to providean excavator having areadily removable lip which does not require rivets for fastening.

Another object of my invention is' to provide, for a generallyelliptical excavator bucket body,

a removable lip extending around more than half of the bucket bodyperiphery and held in place without rivets.

An additional object of my invention is to provide a removable,rivetless lip for an excavator,

which can be installed between successive excavators in line. v

A further object of my invention is to provide an excavator in which theparts fit tightly without the necessity of accurate machining.

Another object of my invention is to provide an excavating body and lipwhich have generally improved fastening means.

Another object of my invention is to provide an excavating body having amajor axis with a detachable lip extending beyond or past such axis.

A further object of my invention is to provide an excavator body and lipin which the forward ends of the lip are held from rearward movement andthe lip is seated to resist digging strains.

An additional object of my invention is to provide a body and lipassembly in which the lip is amply rugged but contains a minimum ofmetal in order .to reduce the amount discarded.

A still further object of my invention is to provide a removable lip foran excavator which can be installed between successive excavators.

The foregoing and other objects are attained in the embodiments oftheinvention illustrated in the drawings, in which- Fig. 1 is a schematicdiagram showing in longitudinal cross-section on a vertical plane anupper portion of a dredge bucket body and its associated lip ininitialassembling position in accordance with my invention.

Fig. 2 is a schematic diagram similar to Fig. 1. showing a successiveassembly stage of the lip and bucket body. v

Fig. 3 is a schematic diagram similar to Fig. 1, showing a furtheradvanced assembly stage of the lip and bucket body.

Fig. 4 is a schematic diagram similar to Fig. 1, showing the lipassembled with the bucket body in accordance with my invention.

Fig. 5 is a schematic diagram in horizontal cross-section, the plane ofwhich is indicated by the line 55 of Fig. 4, of an assembled excavatorin accordance with my invention.

Fig. 6' is afview similar to Fig. 4 but showing a modified form of lipand bucket body assembly.

Fig. 7 is across-section on a vertical, longitudinal plane of apractical form of dredge bucket body and lip assembly in accordance withmy invention.

Fig. 8 is a in Fig. '7.

Fig. 9 is a half cross-section of the excavator shown in Fig. '7, theplane of section being indicated by the line 99 of Fig. '7.

Fig. '10 is a cross-section on a vertical. longitudinal plane of amodified form of excavator in accordance with my invention. Fig. 11 is aperspective side view of the excavator shown in Fig.10.

Fig. 12 is a perspective view of a fastener used with my excavator.

Fig. 13 is a perspective front view of the excavator shown in Fig. 10.

Fig. 14 is a perspective rear view of the excavator shown in Fig. 10.

Fig. 15 is a perspective to an enlarged scale, showing part of a liphorn from the inside.

Fig. 16 is a perspective to an enlarged scale, 75 showing part of a liphorn from the outside.

half-plan of the excavator shown Fig. 1'7 is a perspective to anenlarged scale,

showing, from the inside, part of a bucket body adapted to receive thehorn of Fig. 15.

Fig. 18 is a perspective to an enlarged scale, showing, from theoutside, part of a bucket body adapted to receive the horn of Fig. 16.

Fig. 19 is a cross-section on a vertical, longitudinal plane of afurther modified form of excavator in accordance'with my invention.

Fig. 20 is a perspective side view of the excavator shown in Fig. 19. v

Fig. 21 is a perspective front view of the excavator shown in Fig. 19.

In its preferred form, the excavator of my invention includes a bucketbody having a substantially elliptical margin with which a removmaticdiagram of a dredge bucket body and lip for descriptive illustration ofthe features and principles of my invention, but these figures are notintended to disclose a. practical embodiment of the invention,necessarily. In these figures many of the dimensions are greatlyexaggerated,

.and the location of various of the parts is distorted from usualpractice, for the purpose of illustration. As diagrammatically shown,the excavator body 6 is a cup-like structure having a substantiallycontinuous bounding wall, generally designated 1, having a rear portion8 and a front portion 9. Since-the bucket in use in a continuousconveyor is sometimes upright and sometimes inverted, sometimestravelling from left to right and at other times from right to left, anyreferences herein to upper or lower, forward or rearward, right or left,or horizontal or vertical, are purely relative.

In a cross-section on a transverse, approximately horizontal plane, thecontour of the wall I is virtually elliptical (see Fig. 5), so that themajor axis defining the major vertical plane is represented by thebroken line I I.- This elliptical contour is by no means mathematicallyexact, and wherever mathematical terminologyutilized herein it refersapproximately to the shapes and contours utilized since, due largely tothe casting technique employed, exact accuracy is virtually impossibleand variation between successive pieces.

' This is customarily a cast manganese steel member, matching in contourthe, margin I! of the bucket body 6 and preferably of sufliclent arcuateextent at least in part to project beyond or around the major axis ll.The lip is thus crescentshaped or more than semi-elliptic in plan. Al-

' though it is preferably fabricated in one piece, the lip l3 canconveniently be thought of as havaccuses 3 ing a central portion M, aleft-hand terminus or horn l6, and a right-hand terminus or horn W. Thehorns extend away from the central portion H1 in the same direction andare approximately,

5 although by no means mathematically, parallel. I preferably providemeans for interrelating'the bucket body 6 and the lip l3 in the regionof'the horns l6 and I! in such a way that there are large bearingsurfaces to resist the principal 10 forces encountered in excavating.These forces are represented by arrows I8 and I9, not intendedaccurately to represent the precise amount or direction of the forces ortheir resultants, but to give a general indication of the direction inwhich some of the major forces act. To provide such mating surfaces sothat they can be finished by no more than superficial grinding aftercasting, and so that they will give a tight interrelationship whenmated, I preferably provide on the bucket wall I, in lateral areasadjacent the major axis ll, lateral seating areas 22 and 23, each ofwhich is preferably a surface of revolution about the major axis ll.

Conveniently, the radius of the surface 22 is 25 R1, centering on themajor axis II and located therefore in the central plane 2|, andlikewise being substantially concentric with the external boundingsurface 24 of the bucket wall the radius of which is R (Fig. 5). Thecoincidence in contour of the external surface 24 and of the surface 22of revolution is not necessary but is desirable to give relativelyuniform thickness to the wall i. It is also not at all necessary thatthe surface 22 of revolution be defined by a constant radius R1 so thatit is spherical, since this surface can be ellipsoidal, hyperboloidal,paraboloidal, or an approximation of any suitable surface of revolution,even flat. It is also not necessary that the axis of the surface ofrevolution be precisely coincident with the major axis H of the bucketbody, but a reasonable approximation thereto is desirable. Preferably,the surface 22 of revolution is located at about the mid-point of thethick- 1 ness of the wall i.

Adapted to mate therewith is a corresponding surface 26 of revolution onthe horn it. This surface of revolution, when the parts are assembled,is preferably concentric with the surface 22 of revolution so that itsrepresentative radius R2 centers on the major axis H of the assembly.

The character of the surface 2b of revolution is subject to considerablevariation, but preferably R1 and R2 are made to approach each other asnearly as is commercially feasible for manufacture.

As shown in Figs. 1, 4, and 7, a side elevation of the surface 22 ofrevolution is not a complete circle and may even be elliptical or ofcontour other than circular, as far as its outline is con-= 60 cerned,but the surface or area 22 preferably constitutes a somewhat lunar,shallow recess 3i in the wall 7, opening upwardly onto the margin 52 ofthe bucket and being likewise bounded on what approximates a diameter bya ledge surface 32 formed by an abutment 33 interposed between therecess 3! and the upper margin l2 of the body. There are thus providedin the bucket body two lateral recesses 35, each being approximatelylunar shaped in side elevation, being about 70 half the thickness of thebucket wall, being defined by a surface of revolution approximatelycentered on the major axis of the bucket, and. opening upwardly throughthe upper margin of the bucket. These shallow recesses are distinct 75from virtually closed pockets since they can be accurately cast and areopen to receive finish grinding tools.

Each of the horns l6 and I] on the lip I4, characterized by its surface26 of revolution, is substantially lunar inside elevation to correspond5 generally with the shape of the recess 3|, but the lower margin 36 ofthe horn' is spaced from the margin 33 of the recess so that under nocircumstances is there contact therebetween. The inner surface 6! ofeach horn is preferably sub- 10 stantially a surface of revolutionmatching the mating surface 26 and characterized by a radius R3; and,although this is not a necessary relationship, it is usually establishedin order to provide a uniform horn thickness, the general aim 15 beingto keep the interior periphery 44 of the lip and the interior periphery45.01 the body 6 substantially continuous, smooth and uninterrupted,

' so as to facilitate loading and discharge of the bucket. The top ofeach horn is preferably a 0 flat surface it, designed to abut the ledgesurface 32 on the associated abutment 33, while all of the horn surfacesmerge smoothly into the surfaces defining the rectangular cross-sectionof the remainder of the lip I3. 25

In order that the lip may be appropriately related to and supported onthe bucket, I preferably provide, in accordance with my invention, apair of fulcrum pads il and 48, each of which is a segregated area ofthe margin l2 which projects 30 slightly from the surrounding margin toabut and lie in immediate contact with the undersurface 39 of the lip.When the lip rests upon the fulcrum pads ti and 48, with the surfaces 46of the horns i6 and IT in abutment with the 3 ledge surfaces 32, the lipis substantially located and positioned on 'the bucket body, since themating surfaces 22 and 26 of revolution preclude any movement radiallyof the major axis H, counterclockwise (Fig. 4) rotation is precluded by40 the fulcrum pads ii and the abutments 33, and transverse or lateralmovement along the major axis Ii is precluded by the mating surfaces ofthe two horns.

It thus remains to prevent rotation of the lip 45 it with respect to thebody 6 in a clockwise direction (Fig. 4) when'such rotation is notdesired. For this reason I provide a pair of lugs 54 on the centerportion i i of the lip and a corresponding pair of lugs 52 on therearward part 8 of the 50 body wall 7. These lugs are each apertured toreceive a fastening comprising a headed bolt 53 and a nut 55,. When thenut is screwed tightly upon the bolt, the center portion i l of the lipis drawn toward the margin B2 of the bucket body, 55 and preferably 1'leave sufficient clearance between these two so that the arms it and Hact as levers, being drawn down adjacent the center portion it,fulcrurning on the fulcrum pads ll and pressing tightly against theabutments 33.

The tension put upon the bolts 53 is preferably sumcient to introducespring or a strain into the horns it and ii, so that the parts are, dueto the resiliency of the removable lip itself, held in place under aninitial stress. The lip 33 is finally seated upon the margin E2 toprovide a tight joint. This tension manner of assembly, utilizingaslight leverrocking movement on the fulcrums ll, takes care ofinaccuracies in casting and finish, and yet assures a tight assembly ofthe parts. Relative movement between the lip and the body are precludedin all directions, and the excavating or dredging stresses, as indicatedby the arrows l8 and is, are borne by solid, la ge faces and in no wiseare imposed upon the fastenings 53. Inside and outside flanges have beenomitted from the diagrammatic views in order to simplify them, but suchflanges augment rather than vary the means for preventing shifting ofthe detachable lip on the bucket body.

. With the arrangement of removable lip and bucket body described, thegeneral assembly is effected primarily as shown in Figs. 1 to 5,inclusive, wherein the bucket body 6 is assumed to be interposed betweena preceding and a succeeding bucket in the upper run of a bucket line..By suitable mechanism for gripping .the detachable lip, the lip isfirst poised above the bucket body, with the horns dependingsubstantially above the lunar recesses. The lip is lowered into positionwith pads 56 on the lip horns resting upon the abutments 33 on thebucket body. The major portion of the weight of the lip isthus restedupon the bucket body, so that the lip can readily be positioned forfurther maneuvering without great effort. Following this, the lip is ingeneral rotated about the major axis II in at least an approximatefashion, until it passes through the position shown in Fig. 3 andfinally occupies the position shown in Fig. 4. In this position thehorns are disposed in their respective lunar recesses, the abuttingsurfaces 46 and 32 are in contact, and the lip is resting upon thefulcrum pads 41. The fastening bolts 53 are then put into position andthe fastenings 54 are operated so that the bolts are placed in tensionand the lip is sprung into place.

The rotation of the lip into position is followed in reverse order whenthe lip is lifted out for replacement .or for inspection. The fastenings53 are first loosened and removed, the lip is rotated aboutthe majoraxis II until it occupies substantially a depending position and then islifted approximately vertically upwards from its relationship with thebucket body, coming free without in any wise interfering with the pre-.ceding or succeeding buckets in the line.

Throughout both of the operations of installation and dismounting,therefore, the approximate ro- I curvature of the surfaces is necessaryto prevent radial movement of the mating surfaces, nevere theless in theextreme condition where such mating surfaces are true planes it isdesirable to provide an additional pair of projections 51 at the marginof the lunar recesses 3I to come virtually into contact with theboundaries 36 of the horns, so that movement of the lip I3 to the leftin Fig. 6 is effectively precluded by direct'abutment of these surfaces.These faces of the projections 51 in themselves are partial surfaces ofrevolu-.

tion, so that, even in the extreme case where the mating surfaces 22 and26 are flat, there are still surfaces of revolution effective topreclude radial movement of the lip orf the bucket body.

The foregoing description is primarily of a diagrammatic arrangement, toemphasize a theoretical relationship of parts which is particularlydesirable. In practice, there are usually many factors which becomeimportant to modify the general considerations mentioned. In Figs. 7,

8, and 9 there is shown an example of an actual dredge bucketconstructed in accordance with my invention and incorporating thevarious factors disclosed herein as being of advantage. In the.practical arrangement, the bucket body I06 itself is not, incross-section, a true ellipse, although it approximates the ellipticalcontour, particularly around the left (Fig. 8) side of the major axisI01. In addition, the margin I08 of the body is provided with anexterior ledge I09 on which a depending flange III on the lip II2 restswhen the lip and the bucket are finally assembled. This flange forms anoutside guide and protector on the body, while pads H3 and H4,corresponding to the horns I6 and I1, provide inside flanges.Preferably, the outside flange III and the inside flanges H3 and. H4 onopposite sides of the body I06 are in overlapping relationship toprovide a channel III; or groove therebetween. The margin I08 of thebucket body itself lies within this channel and is consequently wellreinforced and protected by the overlapping flanges against the lateralstrains arising in excavating.

The recesses Ill and H8 are shallow and open for convenience in castingaccurately and so that all of their surfaces are readily accessible to agrinding tool for finishing purposes. It is found in practice that apocket or depression which is relatively deep, low and narrow isvirtually impossible to cast with any satisfactory degree of accuracyand cannot subsequently be ground to reasonable-limits. Consequently,the construction adopted herein, of providing relatively large, shallowand open recesses, permits ready and accurate casting with greatfacility for subsequent grinding or chipping. Since the re- 1 cesses areso readily accessible and can be so accurately cast and finished, it ispermissible to provide a slightly bevelled surface II9 along the seatingpads I2I to abut a comparable bevelled face .on the horn flanges H3 andH4, so that, should there be any tendency to dislodge the horn flangesinwardly toward each other, the tendency will be resisted by theinclined or bevelled faces I I9. While these faces are slightlybevelled, they are nevertheless available for grinding by an appropriatetool.

Another practical embodiment of my invention is disclosed in Figs. 10 to18, inclusive. In this I arrangement the bucket body or hood 20! is acast manganese steel structure integral with the bucket link 202 whichis characterized by a pair of front bosses 203 and 204 pierced toprovide aligned eyes 206 and a rear boss 20'! pierced to provide a reareye 208 for pin connection to adjacent buckets.

transverse axis is located approximately as shown by the point 209 inFig. 10. In general, on one side of the major axis 209 the peripheralmargin 2 of the bucket body is enlarged and thickened and approximatelycentering on the major axis,

are lunar recesses 2I6 adapted to receive mating horns 2II on the lip2Il and having reasonably .accurate surfaces of revolution in immediatejuxtaposition. The horns are provided with seating extensions 2I8 which,when the device is assembled or disassembled, are intended to coact Thebucket body 20I is substanti'ally elliptical in contour, so that itsmajor r with abutments 219 on the body. Fulcrum seats 22I form bearingpads forthe lip, so that fastenv ing bolts 222 are effective to springthe lip somewhat to hold it in position under stress. The fasteningbolts are preferably fabricated, as shown in Fig. 12, with enlarged,flattened, conical heads 223 adapted to seat in complementary recessesin sockets 224 on the lip, and are engaged by nuts abutting lugs 226 onthe body 20L Adjacent the fastening bolts 222 I preferably provideintegral with the hood 20| a pair of guide fins 221 which are intendedprimarily to coact with the next succeeding bucket when the buckets areinverted around the upper tumbler,

15 in order to guide the material discharged or spilled from the nextsucceeding bucket. Thus,

in effect, the pins 221 on one bucket are functional continuations ofthe discharge surfaces of the succeeding bucket.

20 A further modified practical embodiment of the invention is disclosedin Figs. 19 to 21, inclusive, in which the bucket body 306 includes anintegral hood 301 and a' link structure 308 having aligned front eyeapertures 309 and a rear eye 25 aperture 3! I. The body 306 is generallyelliptical 30 which, instead of having surfaces of revolution interiorlyof the hood, are provided with suitable surfaces of revolution 3|9interiorly of the horns but exteriorly of the hood, terminating inabutting surfaces 32! arranged to engage with ledges 35 3.22 on theexterior of the bucket structure. The

outside of the bucket body 306, consequently, has

mating surfaces of revolution and is also provided with fulcrum seats323 as in the case of the inside horn. The recesses in the outside ofthe body are equally available for accurate casting and grinding forfinish, since they are relatively shallow, wide and long. They arelikewise preferably somewhat chamfered or bevelled in order to provide alateral interlock between the projecting horns and the bucket body, andin general follow out the principles of the inside horn except for thefact that they are located exteriorly of the body.

The interior of the body is provided, preferably, with recesses 324 inwhich depending flanges 320 are situated. These flanges preferably haveconsiderable clearance with the interior of the bucket body and with'themargins of the recesses, although they also are preferably defined bysuragainst abrasive wear and also provide extra re-' 30 inforcement atthe lateral portions of the bucket wherein deformation due to diggingstresses on I the lip tends to be greater.

The manner of assembly and disassembly of the outside horn lip issubstantially the same as with the inside horn; that is, each horn has a70 abutting surfaces 32! and 322 in intimate con- 75' other features ofconstruction of my detachable projecting portion 32? which can be restedupon the shoulder 328 of the abutment on the body forming the ledge 322,and can then be substantially rotated into assembled position with thetact, with the lip seated upon the fulcrum pads 323, and with suitablebolt fastenings 32d inltension to hold the lip in position on the bucketunder stress of its inherent resiliency. Various faces of revolutionapproximately mating with' lip and body construction are in generalfollowed in this arrangement.

7 The general characteristics of all of the embodiments of my inventioninclude surfaces of revolution about which the detachable lip and thebody are relatively rotated for assembly and disassembly, for holdingthe lip against dislodgment in all directions of possible motion exceptrotation in one direction, and include holding the lip and the bodyagainst relative rotation in such direction by fastening means whichplace the lip under inherent spring tension on the body. Theconstruction is further characterized by the provision of open recessesfor interlocking with horns on the lip, so that the construction and thefinishing of the bucket and the lip are both attended with considerablepractical facility.

I claim:

1. An excavator comprising a bucket body having an upper margin adaptedto receive a detachable wearing lip, there being a pair of facingrecesses in the inner sides of said body, each recess being in partspaced from said margin to form an abutment between said recess and saidmargin and in part opening upwardly at said margin, a detachable wearinglip adapted to seat on said upper margin, a pair of enlarged hornsdepending from the inner sides of said lip substantially 0ccupying saidrecesses and contacting said abutments, a flange depending from theouter side of said lip and abutting the sides of said body toresistlateral thrusts tending to dislodge said horns from said recesses, andfastening means for holding said lip on said body 2. An excavatorcomprising a bucket body having an upper margin adapted to receive a.detachable wearing lip, there being a pair of facing recesses in theinner sides of said body each of said recesses being bounded by asubstantially semi-circular wall and a radial wall to provide an upwardopening to said margin and a ledge between said recess and said margin,a detachable wearing lip adapted to seat on said upper margin, a pair ofsubstantially semi-circular horns sides of said body to resist lateraldislodgment of said horns from said recesses, and fasteners for drawingsaid lip into tight abutment with said body.

3. An excavator comprising a bucket body having an upper margin adaptedto receive a detachable wearing lip, a detachable Wearing lip adapted toseat on said upper margin, a flange depending from the exterior of saidlip and abutting the sides of said body, a. pair of horns each dependingfrom the inside of said lip at the sides thereof to overlap the end% ofsaid flange, there being substantially semi-circular recesses in theinner side walls of said body to receive said horns with the exposedsurface thereof substantially flush with the inner surface of said body,and fastening means for holding said lip and said body in abutment.

4. An excavator comprising a bucket body having an upper margin adaptedto receive a detach- 5. An excavator comprising a detachable C- shapedwearing lip for a bucket body, an exterior flange depending from thecentral portion and the sides of said lip and a pair of horns dependingfrom the inner sides of said lip, each of said horns having asubstantially semi-circular contour below the sides of said lip and asubstantially radial portion adapted to abut an overhanging ledge onsaid bucket body.

6. An excavator comprising a bucket body having an upper margin adaptedto receive a detachable wearing lip, there being a pair of facing

